A. Technical Field
The present invention relates to signal processing of electronic sensors, and more particularly, to systems, devices, and methods of reducing errors in angular rate sensor circuits.
B. Background of the Invention
In some circuit applications, such as in MEMS sensor circuits, the phase difference between a desired signal, such as a sinusoidal waveform of a Coriolis signal generated by a gyroscope and a demodulation phase signal, such as a quantized sinusoidal waveform, must be kept as small as possible to reduce undesired effects, such as offset dependency on the acceleration signals. Some existing approaches estimate a demodulation phase or determine a value based on analytical modeling. The value estimated or calculated at the design level remains associated with the demodulation phase during regular circuit operation. Traditional approaches do not measure and calibrate the demodulation phase and, thereby, fail to take advantage of potential improvements in the rejection of external disturbances, such as acceleration errors.